Persist setTimeout and setInterval across Node.js restarts


I set quite a few server-side timeouts with setTimeout and setInterval for each connected user that can last for 10-30 seconds. If the Node.js instance restarts in the middle of one of these timeouts, they are obviously all cleared on restart, which can cause some issues for these users. How would I go about persisting these timeouts, or are there any modules that already help with this?

Problem courtesy of: James Simpson


I would store the start times and durations in Redis and restart incomplete timers when your application reloads. Some Redis modules:

Solution courtesy of: Loc Nguyen


setTimeOut takes delay as parameter, so when setting timeout, capture 'currentServerTime + delay' say 'serverTriggerTime' and persist this in DB. Then, on restart of server, create the same timer using the serverTriggerTime. Then, delay = serverTriggerTime - currentServerTime, use this delay to set new timer.

When setting timer

const date =;
const serverTriggerTime = +date +  +delay; //time in milliseconds

On server restart:

serverTriggerTime = //retrieve from DB.
newDelay = serverTriggerTime -;

Also, set new timer only if newDelay >= 0, meaning the trigger time has not reached and will happen after newDelay time.

Discussion courtesy of: Sundeep

This recipe can be found in it's original form on Stack Over Flow.